OTGW: pin18 not changing from 0-5V when pin3 to GND [SOLVED]

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PeterP
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Re: OTGW: pin18 not changing from 0-5V when pin3 to GND [SOLVED]

Post by PeterP »

Investigated this situation somewhat more. Can it be that you mixed Q4 and Q5 (BC548 versus BC558)? You easy can make this mistake due to the PCB layout. Potentially you also will detect a too high +5 voltage, thinking the 7805 regulator is defective. In case of mix-up of Q4/Q5: replace both transistors with new ones.
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